1. Field of the Invention
This invention relates to compositions and methods for controlling bacterial growth, and more particularly to anti-bacterial agents and their methods of use.
2. Description of the Related Art
Bacterial infections remain a public health concern, and indeed a growing one in view of increasing resistance to existing drugs by pathogenic bacteria. Drugs now in use fall into a relatively small number of chemical classes, and operate by one of a relatively small number of mechanisms. Development of resistance to one drug can therefore adversely affect the efficacy of others. Moreover, because bacteria can exchange genetic information, resistance can spread from one species to another.
It is therefore desirable to have new classes of anti-bacterial agents based upon novel mechanisms of action, to which bacteria are unlikely to have resistance.
In addition, bacteria in nature commonly grow attached on solid surfaces in a mode of growth referred to as a biofilm. Bacteria within biofilms differ physiologically from those grown in liquid culture (planktonic cells) in having increased resistance to environmental stresses (such as antibiotic treatment). In clinical environments, biofilms of pathogenic bacteria lead to persistent and chronic infections refractory to treatment with conventional antibiotics. The U.S. Centers for Disease Control estimate that 60% of bacterial infections involve such biofilms. Industrially, biofilms contaminate and clog water lines, foul surfaces and contribute to corrosion and decay. Not all the consequences of biofilm formation are deleterious, however; for example, in bioproduction processes biofilms help in maintaining a stable population of cells as substrate passes through a bioreactor.
Consequently it is desirable not only to have new classes of anti-bacterial agents, but also to have ways of promoting and/or inhibiting the formation and maintenance of bacterial biofilms.